The AR15.Com Ammo Oracle

History and Basic Design of .223 and 5.56 Ammunition.

Performance of .223 and 5.56 Ammunition.

Terminal Performance of .223 and 5.56 Ammunition.

.223 and 5.56 Ammunition Testing

Selection of .223 and 5.56 Ammunition.

Ammunition recommendations from the authors of the AR15.com Ammo-Oracle.

Purchase and Storage of .223 and 5.56 Ammunition.

Legal questions.

Miscellaneous .223, 5.56 and Other Ammunition Questions.

Ammo Oracle

Q. What is the circle-cross stamp on some of my ammo?

The circle-cross Å is the NATO symbol.  It indicates that the ammo was loaded in a NATO-approved facility and meets the NATO specifications for that round.  Note that NATO specifications are not the same as US military specifications and that many NATO-approved rounds do not meet US military specs.  US military specs (such as M193 and M855) have additional requirements, such as minimum velocities, that the NATO specs (like SS-109) don't have.

Fact: There are some exceptions to this rule.  For example, recent Lake City and Winchester M193 is loaded in cases marked with the NATO circle-cross.  This is done simply to save money by having one production run of cases instead of two.  M193 was never adopted by NATO; by the time NATO decided to standardize on 5.56mm, the SS-109/M855 ammo was available, and was adopted as the standard.  M193 is still "Mil-Spec," it just isn't "NATO" spec.